Hand torch



June 2, 1959 W, UNDGREN 2,888,979

HAND TORCH Filed June 29. 1954 ZJ J7 HAND TORCH William L. Lindgren,Sycamore, Ill., assignor to The Turner Brass Works, a `corporation ofIllinois Application June 29, 1954, Serial No. 439,967

1 Claim. (Cl. 158-33) This invention relates to a hand torch and, morepartictates Patent O ularly, to a hand torch having a disposable fueltank and a unitary valve assembly and burner means detachably connectedthereto.

An object of this invention is to provide a new and improved hand torch.

Another object of this invention is to provide a hand torch having afuel tank and a unitary valve assembly and burner means detachablyconnected thereto whereby the valve assembly and burner means may bedetached from the fuel tank when the tank is empty and secured to a fulltank for subsequent use of the hand torch and wherein the n A2,888,979Fatented June 2, 1959 ,t ice vention in vertical section and with partsof the angle tube and tank omitted;

Fig. 3 is a view taken along the line 3-3 of Fig. 2; and,

Fig. 4 is a view taken along line 4-4 of Fig. 2.

While this invention is susceptible of embodiment in many dierent forms,there is shown in the drawings and will herein be described in detail anillustrative embodiment of the invention with the understanding that thepresent disclosure is to be considered as an exemplification of theprinciples of the invention and is not intended to limit the inventionto the embodiment illustrated. The scope of the invention will bepointed out in the appended claim.

In a preferred form of the invention, the hand torch embodies acylindrical fuel tank containing liqueed petroleum fuel or the like, anda valve assembly 13 for regulating ilow of gas through conduit meanssuch as an angle tube 14 for ignition at a burner means 15 carried atthe end of the angle tube 14.

The tank 10 has a pressure relief valve 11 comprising a valve housing 16which may be brazed to the tank. A

" stem 17 in the housing 16 extends through an opening valve assembly isconstructed so that the maximum number of necessary cooperating partsbetween the tank and valve assembly are carried by the valve assembly toreduce the wastage incurred by disposal of the empty tank.

Another object of the invention is to provide a hand torch having atank, valve assembly, and burner means, said burner means including ahollow cylindrical tube and an insert having a longitudinal bore and aplurality of 1ongitudinal grooves on its outer periphery press-littedinto engagement with the inner periphery of the hollow tube, theconstruction and arrangement being such that thecombustion mixturepasses through the passages formed by the grooves on the periphery ofthe insert and through the bore therein to form a circular array offlame jets with a flame centrally disposed therein at a positionexternally of the hollow tube.

Another object of the invention is to provide a hand torch having a fueltank and a valve assembly connected thereto, wherein the valve assemblyincludes a valve body secured to the tank and has passage meanstherethrough leading from an inlet end to an outlet end, and valve meansfor controlling ow of fuel through the passage means in the valve bodyincluding a hollow cylindrical packing member mounted in the valve body,a valve stem threadably mounted in said packing member and having an endpositioned for controlling the open or closed position of said passagemeans and means coacting between the packing member and the valve stemfor limiting the open position of the valve.

Another object of the invention is to provide a hand torch having a fueltank and a valve assembly and burner means connected thereto, whereinthe valve assembly has a valve body connected to the tank and passagemeans therein leading from the fuel tank outlet to the burner means,spring-urged check means in one of said passages being operable to stopthe flow of fluid from the tank when the back gas pressure developedbetween the burner and the check means becomes greater than the gaspressure in the tank so as to provide a substantially even flame at theburner.

Further objects and advantages will become apparent Fig. 2 is anenlarged side elevational View `of the in- 1S in the bottom of thehousing and a rubber washer 19 on the bottom of the stem acts to sealopening 18 when urged down into closed position by a spring 2l) pressingon a ball 21 slidably mounted in the housing 16. The washer 19 unseatsto vent excess pressure through housing 16 to atmosphere, the pressureat which the valve vents being controlled by the position of a threadedstud 22 having a passage 22a and which may be shifted to vary the forceof the spring 20.

A tank outlet member 12 brazed to the tank is provided with a bore 23threadably receiving a mechanical type valve, such as a conventionaltire valve 24, which permits egress of fuel from the tank as shown bythe arrows upon depression of the valve core 25 to the position shown inFig. 2.

` The valve assembly 13 comprises a valve body 26 having a threaded bore27 threaded on the burner inlet `12 and a coaxial threaded bore 28 forreceiving a valveoperating member 29, the bottom of which engages anddepresses the valve core 25 when valve body 26 is secured on the tank. Asmall opening 30 is provided near the bottom of ymember 29 and connectsa portion 23a of bore 23 above the tank valve 24 and a bore 31 in themember 29 to permit gas to pass from the tank 10 to the bore 31.Surrounding the valve-operating member 29 and disposed in a groovetherein is a rubber O-ring 30a which slides snugly in the portion 23a ofbore 23 to prevent the escape of fuel as valve-operating member 29 isinserted in the tank outlet member 12 and begins to depress the valvecore 25 in the tank. It will thus be seen that the valve assembly 13 isreleasably connected to the tank l0 and that when a tank is empty, thevalve assembly may be placed on a full tank. When the tank 10 and valveassembly 13 are assembled, a washer 32 and a gasket 33 make an air-tightconnection between the parts.

An upper portion 31a of bore 31 is enlarged to provide a curved shoulder34 facing away from the gas flow and providing a seat for check meanssuch as a ball check valve 35 urged to a closed position by a spring 36.The ball check 35 is normally unseated by gas pressure in the tank 10 topermit 'liow of fuel but acts to prevent flow of fuel from the tank 10whenever the back gas pressure developed between burner means 15 andcheck valve 35 combined with the pressure of the check spring 36 becomesgreater than the gas pressure in the tank, closing check valve 35. Asthe back pressure is gradually reduced due to the passage of fuelthrough the burner means 15, the pressure in the tank 10 again openscheck valve 3S to allow the passage of fuel from the tank 10. This cycleis continually repeated whenever the torch is in operation and tends toprovide a substantially even ame at burner means 15, the cycle beingaccelerated when liquid fuel passes beyond the check means because ofthe pressure created by its vaporization. flowing past the ball check 35passes from bore 31a into a passage 38 having a cross passage 39 whichconnects with a control valve chamber 42 and a passage 43. Fuel iiowsfrom the passage 43 through the angle tube 14 to the burner means 15.

In order to control the flow of fuel from the tank to the burner means15, a control valve in the form of a needle valve 41 is provided. Thisvalve has a valve stem 40 provided with an end 44 which is shaped toclose the cross passage 39 in one limit position (as in Figs. 2 and 4)and to permit unrestricted fiow through the cross passage in its otherlimit position. The control valve 41 is seated in a threaded bore 44 inthe body 26 of the valve assembly 13. A packing member in the form of asleeve 47 is threadably received in the bore 44 and abuts against awasher 45 fitted against an O-ring 46. 'Phe valve stem 40 has threads 48which engage threads 49 on the inner wall of the packing member 47 sothat rotation of a knob 50 on the valve stem will vary the position ofthe valve stem end 44 with respect to the cross passage 39. The packingmember 47 is provided with a shoulder 51 which engages the outer edge ofthe threads 48 on the valve stem to limit the opening movement of thevalve. v

The angle tube 14 carrying the burner means 15 is threadably received inthe upper end of the valve body 26. As best shown in Fig. 2, a fillerrod 52 is loosely tted in the angle tube to reduce the cross-sectionalarea within the tube while allowing gas to flow between the filler rod52 and angle tube 14. The filler rod 52 terminates short of the angletube 14 to allow for positioning of an orifice block 53 having anorifice 53a within the angle tube.

A primary tube 54 is threadably received on the end of the angle tube 14and has a shoulder portion 55 mating with the top of the orifice block53. A longitudinal bore 56 is provided in the primary tube 54 forcommunication with the orifice 53a in the orifice block. A plurality ofradial openings 57 are provided in the primary tube through which airenters the bore 56 to mix with the fuel passing therethrough. The upperend of the primary tube is of a reduced outer diameter so as to formwith a portion of the inner periphery of a cylindrical hollow mixer tube59 having a lower sleeve portion 60 threadably received on the free endof the primary tube 54 an annular chamber 58. A cylindrical flame tube61 is press fitted onto the sleeve portion 60 of the mixer tube 59. Anannular chamber 63 is formed between the inner periphery of the flametube 61 and the upper portion of the mixer tube 59 above the sleeve 60.A bore 64 into which the upper end of the primary tube 54 extends isprovided in the mixer tube 59 extending through to the upper end thereofand in communication with a plurality of radial passages 65 provided inthe mixer tube 59 which open to the annular chamber 63.

A mixer tube insert, which may be formed by the extrusion process, 66 ispress fitted into the open end of the bore 64 and comprises agear-shaped lower portion 67 provided with a plurality of equally-spacedgrooves 68 around its periphery which form with the inner periphery ofthe mixer tube 59 a plurality of passages 68 communicating with the bore64. A portion 69 of the mixer tube insert extends beyond the end of themixer tube 59 and is pierced by a longitudinal bore 70 which is bevelledat both ends and is in communication with the bore 64. Fuel passingthrough the orifice block 53 flows through the bore 56 and mixes withair flowing through the passages 57. The mixture flows out the end ofbore 56 and the flow is then divided so that a certain amount passesthrough the passages 65 and through the chamber 63, through passages 68between the mixer tube 59 and mixer The .fuel

4 tube insert 66, and through the bore 70 to be ignited at the upperopen end of the llame tube 61 to forma series of jets disposed in acircle with a central jet disposed within the circle.

I claim:

In a liquefied petroleum appliance, a fuel tank containing a supply ofliquefied petroleum fuel at increased pressure and having a conduitmeans connected thereto forming a passage extending from said fuel tankto a point 0f fuel utilization, a burner unit in one end of said conduitmeans at the point of fuel utilization operative as a restriction andeffecting a build-up of back gas pressure in said passage, and a valveassembly in the other end of said conduit means to control the admissionof fuel at increased pressure into said passage from said fuel tank,said passage having a valve seat formed therein intermediate said burnerunit and said fuel tank, a movable valve engageable against said seat, aspring in said passage between said movable valve and said burner unit,said movable valve having a pressure responsive surface bottoming oneend of said spring and being subject to back gas pressure developed insaid passage between said burner unit and said movable valve, said valvemember having `a seating surface subject to the pressure in the fueltank, said pressure-responsive surface and said seating surface of saidmovable valve being proportioned and said spring exerting a biasingforce such that the forces provided by said spring together with theback gas pressure acting on said movable valve exceed the forces actingon said movable valve resulting from the pressure of the fuel in saidfuel tank, thereby temporarily closing said movable valve against saidseat, whereupon said back gas pressure is reduced by consumption of thegas at the burner unit, whereupon said movable valve will automaticallycycle between closed and open positions, a second valve seat formed insaid passage between said movable valve and said burner unit, and avalve engageable with said second valve seat and having a portionextending outside of said conduit means into an accessible position forselectively opening and closing said passage and for selectivelyinitiating automatic regulation of said passage by said movable valve,said burner unit including a mixer tube having a cylindrical bore, and amixer tube insert member comprising a generally `cylindrical disc havinga circumferential row of alternating peripheral ribs and groovesextending in an axial direction and said ribs lhaving an outer diametercorresponding to the inner diameter of said cylindrical bore, said discbeing inserted -in firm assembly in one end of said cylindrical bore andtogether with said mixer tube forming a plurality of separatedcircumferentially spaced passages each communicating at one end withsaid bore and discharging outwardly of said mixer tube, said mixer tubeinsert having a centrally disposed orifice formed therein extendingaxially therethrough concentrically inwardly of said grooves, wherebythe fuel will be burned in the form of a series of circularly disposedjets with a central jet disposed within the circle.

References Cited in the file of this patent UNITED STATES PATENTS

